Urinary Stones in Adults: Essential Tests for Accurate Diagnosis

Urinary stones, or urolithiasis, are a common condition affecting both men and women, most frequently between the ages of 30 and 50. Proper diagnosis and testing are crucial for treatment and preventing recurrence.

What is a Urinary Stone?

A urinary stone, also known as urolithiasis, is a solid mass, often crystalline in nature, that gradually forms in the urinary tract. These stones can vary in size, ranging from tiny particles known as urinary sand to larger stones several centimeters in diameter. They are commonly found in the kidneys, ureters, bladder, or urethra.

What Causes Urinary Stones?

Urinary stones form due to a combination of factors, with insufficient hydration being the most significant. When a person does not consume enough fluids, the urine becomes concentrated, increasing the risk of crystal formation. Other contributing factors include metabolic or nutritional imbalances, such as an excess of calcium or uric acid in the urine. In some cases, chronic urinary infections can also promote the development of urinary stones.

Key factors contributing to stone formation include:

• Dehydration leading to concentrated urine.
• High calcium or uric acid levels in the urine.
• Chronic urinary infections.

Symptoms of Urinary Stones

The symptoms of urinary stones can vary depending on the size and location of the stone. Often, stones are discovered during an acute episode of severe pain, known as renal colic, or during chronic episodes characterized by symptoms such as:

• Severe flank pain (renal colic).
• Hematuria (blood in the urine).
• Recurrent urinary tract infections.
• Painful urination.

In some cases, urinary stones can be completely asymptomatic, only being detected during imaging for other health concerns.

Key Laboratory Tests for Urinary Stones

Laboratory tests play a crucial role in understanding the underlying causes of urolithiasis and in preventing stone recurrence. Several tests are typically recommended, including both blood and urine tests.

Blood Tests:

1. Calcium levels.
2. Proteins (Protides).
3. Uric acid levels.
4. Creatinine and glomerular filtration rate (GFR) to assess kidney function.
5. Fasting glucose to rule out diabetes.
6. Vitamin D (25OH) levels to check for deficiencies that may contribute to stone formation.

Urine Tests:

1. Urinary infection screening: A urine culture (urine cytobacteriological exam) to detect bacterial infections that can contribute to stone formation.
2. 24-hour urine analysis: This test measures key biochemical markers such as creatinine, calcium, sodium, uric acid, and urine pH. These measurements help detect abnormally high levels of substances that promote stone formation.
3. Morning urine density: Measuring urine density in the morning can help evaluate whether the urine is concentrated or diluted, which is a factor in stone formation.

Chemical Analysis of the Urinary Stone

The most critical step in understanding why a urinary stone forms is conducting a chemical analysis of the stone itself. This analysis reveals the composition of the stone—whether it consists primarily of calcium oxalate, uric acid, or other compounds—which helps healthcare providers develop a targeted treatment plan.

Healthcare professionals often refer to the stone as the “hard drive” of the lithogenic process because its composition provides valuable insights into the factors that led to its formation.

How Are Urinary Stones Treated?

In many cases, small urinary stones can pass naturally through the urinary tract without intervention. However, when stones measure several millimeters or larger, medication may be prescribed to help facilitate their expulsion.

Medical and Surgical Treatments:

• Medications: Drugs that relax the muscles in the ureter can help small stones pass more easily.
• Surgical intervention: If the stone does not pass on its own, various surgical techniques may be used, such as:
  • Lithotripsy: A non-invasive procedure that uses shock waves to break up larger stones.
  • Laser fiber treatment: A minimally invasive method using lasers to fragment the stone.
  • Conventional surgery: In rare cases, open surgery may be required if other treatments are unsuccessful.

How to Collect a Urinary Stone?

It is essential to collect any stone passed naturally to ensure proper analysis. Do not discard the stone in the toilet. In the past, filtering urine through paper was common practice, but this method is both inconvenient and unhygienic. Today, urine filters like the Pi-Box are available and make it easier to collect stones. Passing a stone can take several days or even weeks, so it’s important to filter all urine during this period.

What Should I Do with My Collected Stone?

Once a stone is collected, it should be submitted to a laboratory such as Cerballiance for a complete chemical analysis. This analysis, covered by Social Security, provides critical information for two main reasons:

1. It helps guide treatment by addressing the underlying causes of the stone.
2. It reduces the risk of recurrence, as understanding the stone’s composition allows healthcare providers to recommend dietary and lifestyle changes that can prevent future stone formation.

Preventing Recurrence of Urinary Stones

Once the stone has been analyzed, your doctor may recommend dietary adjustments and lifestyle changes to prevent future stones. Key preventive measures include:

• Increasing fluid intake: Drinking plenty of water to keep urine diluted.
• Reducing intake of oxalate-rich foods: Foods such as spinach, nuts, and chocolate can contribute to calcium oxalate stones.
• Managing dietary calcium: Too much or too little calcium in the diet can increase the risk of stones.
• Limiting sodium: High sodium intake can increase calcium excretion in the urine, promoting stone formation.
• Monitoring uric acid: If stones are caused by excess uric acid, a diet low in purines (found in red meat, seafood, and alcohol) may be recommended.

Conclusion

Urinary stones (urolithiasis) are a common health issue that can range from asymptomatic to severely painful episodes. Early diagnosis and proper testing are essential for determining the underlying cause of stone formation and preventing recurrence. By conducting comprehensive blood and urine tests, alongside a chemical analysis of the stone itself, healthcare providers can develop an effective treatment plan that addresses the root cause and minimizes the risk of future stones.

If you pass a urinary stone, remember to collect and submit it for analysis, as this can provide valuable insights for your future treatment and help prevent the recurrence of stones.

For accurate testing and diagnosis, contact your Cerballiance laboratory today.